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pstopnm - convert a PostScript file into a portable anymap
pstopnm
[-stdout] [-forceplain] [-help] [-llx s] [-lly s] [-landscape] [-portrait] [-nocrop]
[-pbm |-pgm |-ppm] [-urx s] [-ury s] [-verbose] [-xborder n] [-xmax n] [-xsize f]
[-yborder f] [-ymax n] [-ysize n] psfile[.ps]
Reads a PostScript
file as input. Produces PBM, PGM, or PPM files as output. This program simply
uses GhostScript to render a PostScript file with its PNM device drivers.
If you don't have GhostScript installed (invoked by a gs command), or
the version you have installed was not built with the relevant PNM device
drivers, pstopnm will fail. You can see if you have the proper environment
by issuing the command gs --help . If it responds and lists under "Available
Devices" pbm, pbmraw, pgm, pgmraw, pnm, pnmraw, ppm, or ppmraw, you're
in business.
pstopnm does not use the Netpbm libraries to generate the
output files, so may not be entirely consistent with most Netpbm programs.
psfile[.ps] is the name of the input file. .pstopnm will add the ps to
the end of the name you specify if no file exists by the exact name you
specify, but one with added does. Use - to indicate Standard Input.
If
you use the -stdout option, pstopnm outputs images of all the pages as
a multi-image file to Standard Output. Otherwise, pstopnm creates one file
for each page in the Postscript document. The files are named as follows:
If the input file is named psfile.ps, the name of the files will be psfile001.ppm,
psfile002.ppm, etc. The filetype suffix is .ppm, .pgm, or .pbm, depending
on which kind of output you choose with your invocation options. If the
input file name does not end in .ps, the whole file name is used in the
output file name. For example, if the input file is named psfile.old, the
output file name is psfile.old001.ppm, etc.
Note that the output file selection
is inconsistent with most Netpbm programs, because it does not default
to Standard Output. This is for historical reasons, based on the fact that
the Netpbm formats did not always provide for a sequence of images in a
single file.
Each output file contains the image of a rectangular part
of the page to which it pertains. The selected area will always be centered
in the output file, and may have borders around it. The image area to be
extracted from the PostScript file and rendered into a portable anymap
is defined by four numbers, the lower left corner and the upper right corner
x and y coordinates. These coordinates are usually specified by the BoundingBox
comment in the PostScript file header, but they can be overridden by the
user by specifying one or more of the following options: -llx, -lly, -urx,
and -ury. The presence and thickness of a border to be left around the image
area is controlled by the use of the options -xborder and -yborder. If pstopnm
does not find BoundingBox parameters in the input, and you don't specify
image area coordinates on the command line, pstopnm uses default values.
If your input is from Standard Input, pstopnm does not use the BoundingBox
parameters (due to the technical difficulty of extracting that information
and still feeding the file to Ghostscript), so you either have to specify
the image area coordinates or take the default.
Unless you specify both
output file width and height, via the -xsize and -ysize options, pstopnm
maps the document into the output image by preserving its aspect ratio.
It has been reported that on some Postscript Version 1 input, Ghostscript,
and therefore pstopnm, produces no output. To solve this problem, you
can convert the file to Postscript Version 3 with the program ps2ps. It
is reported that the program pstops does not work.
- -forceplain
- forces
the output file to be in plain (text) format. Otherwise, it is in raw (binary)
format. See pbm(1)
, etc.
- -llx bx
- selects bx as the lower left corner x
coordinate (in inches).
- -lly by
- selects by as the lower left corner y coordinate
(in inches).
- -landscape
- renders the image in landscape mode.
- -portrait
- renders
the image in portrait mode.
- -nocrop
- does not crop the output image dimensions
to match the PostScript image area dimensions.
- -pbm -pgm -ppm
- selects the format
of the output file. By default, all files are rendered as portable pixmaps
(ppm format).
- -stdout
- causes output to go to Standard Output instead of to
regular files, one per page (see description of output files above). Use
pnmsplit to extract individual pages from Standard Output.
- -urx tx
- selects
tx as the upper right corner x coordinate (in inches).
- -ury ty
- selects
ty as the upper right corner y coordinate (in inches).
- -verbose
- prints processing
information to stdout.
- -xborder frac
- specifies that the border width along
the Y axis should be frac times the document width as specified by the
bounding box comment in the PostScript file header. The default value is
0.1.
- -xmax xs
- specifies that the maximum output image width should have a
size less or equal to xs pixels (default: 612).
- -xsize xsize
- specifies
that the output image width must be exactly xs pixels.
- -yborder frac
- specifies
that the border width along the X axis should be frac times the document
width as specified by the bounding box comment in the PostScript file header.
The default value is 0.1.
- -ymax ys
- specifies that the maximum output image
height should have a size less or equal to ys pixels (default: 792).
- -ysize ys
- specifies that the output image height must be exactly ys pixels.
The program will produce incorrect results with PostScript files that
initialize the current transformation matrix. In these cases, page translation
and rotation will not have any effect. To render these files, probably
the best bet is to use the following options:
pstopnm -xborder 0 -yborder
0 -portrait -nocrop file.ps
Additional options may be needed if the document
is supposed to be rendered on a medium different from letter-size paper.
gs(1)
, pstofits(1)
, pnmtops(1)
, psidtopgm(1)
, pbmtolps(1)
, pbmtoepsi(1)
,
pnmsplit(1)
Copyright (c) 1992 Smithsonian Astrophysical Observatory
PostScript is a Trademark of Adobe Systems Incorporated.
Alberto Accomazzi, WIPL, Center for Astrophysics.
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